Devices of this type are known which comprise a film which covers at least one layer of polyurethane and a drainage tube, which is applied to the lesion and to which a connecting valve is connected which allows connection to aspiration means.
For medications inside the lesion and for performing occlusive medications, particularly if the lesions are of the cavitary type, the filling of the cavitary lesion with a first layer of polyurethane for the plug (application of polyurethane in contact with the lesion) is performed, followed by the application of an expanded polyurethane compress for drainage.
In a first type of known device, a drainage tube is inserted within the cavitary lesion and then such cavity is closed by applying an adhesive film.
Another type of device blocks the cavity with an adhesive film and by resting a flared connection, connected to the drainage tube, in contact with the polyurethane compress.
In any case, the tube is connected to the aspiration means, thus allowing to aspirate serum, exuded matter and liquids to be removed.
A device of this type has unwanted drawbacks and problems.
First of all, the application of the draining tube, which moreover in some cases can be unpleasant for the patient, is rather complicated and requires the intervention of qualified personnel.
Further, devices of this type are scarcely practical, since often it is necessary to limit contact between the film and the skin of the patient, which is particularly irritable and sensitive in the region affected by the lesion.
However, in such devices, when the liquids to be removed are aspirated, bleeding problems often arise due to the aspiration effect at the lips of the cavity. In addition to this, due to the irregular shape that these cavities have, the adhesion of the film to the skin is not perfect, and this leads to infiltrations of air in the drainage pouch, and therefore asepsis of the method and vacuum are not ensured.
Finally, in some circumstances, for example on lesions located in the region of the lower back or buttocks, the patient compresses the film and the cannula with his/her body, applying pressure to the connecting valve: this contact between the connecting valve and the part affected by the lesion not only causes pain but can worsen the conditions of the lesion.
To avoid this, the patient is often forced to stay in very uncomfortable positions for the entire duration of the drainage, which may even reach 72 hours.
Ultimately, the method of the type described entails that the polyurethane is manipulated several times: a first manipulation which serves to position the plug, a second manipulation to arrange the polyurethane compress, a further manipulation to ensure occlusion of the cavity by applying the adhesive film and finally a fourth manipulation for connecting the tube to the double layer of polyurethane and the film.
This method, in addition to being laborious and slow, also provides for the intervention of specialized personnel capable of applying the film correctly and of providing the hole for the tube.
Further, the continuous series of manipulations of the wound, in addition to being awkward and painful for patient, may also entail a greater risk of bacterial contamination.